Role of endoscopic ultrasound-guided fine-needle aspiration in the diagnosis and classification of lymphomas.

Background: endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe and effective technique in the diagnosis of mediastinal and abdominal masses. However, the usefulness of EUS-FNA in the diagnosis and classification of lymphomas is controversial. The aim of this study was to determine the yield of EUS-FNA in the diagnosis and classification of lymphomas.

Methods: a retrospective case series was performed in a tertiary referral center. All consecutive patients referred for EUS-FNA with a suspected diagnosis of lymphoma from March 2013 to June 2019 were included.

Results: thirty-five patients (54.3 % women, median age 72 years) were included. The most frequent location of the node was the abdomen (67.9 %). Nodes were punctured using a 22-gauge (85.7 %) and 19-gauge needle (14.3 %) with a slow-pull technique. The number of passes performed were three or more in 82.9 % of patients. The samples were processed by the cellblock method. Adequate samples for immunohistochemical and molecular biological study were obtained in 33 (94.3 %) patients. EUS-FNA correctly diagnosed lymphoma in 30 out of 35 patients (85.7 %), and subclassification was determined in 23 patients (65.7 %). The most frequent diagnosis was non-Hodgkin lymphoma (85.7 %). There was one moderate adverse event (bleeding), which was resolved during the procedure.

Conclusions: EUS-FNA may be a valuable technique in the evaluation of suspected lymphomas with an adequate diagnostic yield and a very low rate of adverse events.